Olanzapine shouldn't block gabapentin or block tobacco or coffee. What I will say about it is prepare to be hungry having been off and on it for the past ten years trust me when I say that. I've also been on gabapentin and then got moved on to pregabalin which I'm on now alongside olanzapine (with numerous other head meds.)
Hope that helps

I don't notice that it interferes with pregab I'm on pregab coz I messed up my back and they won't prescribe me opiates due to being a long time heroin user who got clean (i still dabble like the idiot I am but not to the extent that I used to)

For me zyprexa numbs emotions. Also you build tolerance to gabas really really fast. But if I have a few days taking bear minimum pregab then take loads then I will feel the pregab drunk and happy feeling.

Olanzapine doesn't act very much on GABA receptors. That is what they mean by "low affinity".
I'll see if I can explain this pretty well, although i am not good at explaining stuff in the slightest: Olanzapine is a dopamine antagonist. It works by attaching itself to dopamine receptors and blocks all the dopamine that wants to be where the Olanzapine is. It does the same thing with serotonin receptors as well (5-ht2a in particular). When you take this drug it kicks all the dopamine and serotonin out and fills the receptor, causing the opposite effects of dopamine and such.
It has little to no impact on GABA receptors, which pregabalin and gabapentin work on. They do not interact with each other directly.
Now you may find that the pregabalin or gabapentin doesn't feel as good as it usually does when you take Olanzapine, this is because of downstream effects on dopamine. The "feel good" you get from lyrica and gaba is from dopamine, which the Olanzapine is now blocking, so you will probably feel more sedated than euphoric.

zyprexa (olanzapine) has been known to blunt a receptor that will not let you experience any substance you take at all. it mostly happens in injection form but it has been know to happen in pill form on rare occasions. when it comes to doing drugs, it's a similar experience shared between people generally speaking. when it comes to psych meds it usually depends on the person. taking it on a individual case by case basis.

that being said it's not guaranteed to not make you feel substances anymore but if you are not then it's most likely the zyprexa.

it's that 5HT2A receptor that can be blunted and not allow you to experience any substance at all. i've heard this quiet a bit in trying to help people get over what has happened from it. (there are 4 psych med injections that blunt this receptor and end up making people not feel substances)

there is a list of side effects of zyprexa you would benefit from looking into if you haven't already.

giving it some time for you body and brain to rid itself of the zyprexa itself as well as the experience of it; in addition to eating healthy, drinking water and exercising will help you get to a good place to gauge what's going on for yourself.

Olanzapine is a Dopamine-2 receptor antagonist. This will cause some blunting the ability to feel good/sense of reward from other drugs which stimulate dopamine. This includes cigarettes, but coffee not really. With gabapentin, olanzapine will not block any of the action of gabapentin, at least in terms of medical usage. I suppose it is possible for gabapentin to lead to some dopamine release, but if so, not much.

You are likely taking the olanzapine for something going on in the brain which is characterized by excess dopamine. Usually this medicine is prescribed for psychotic disorders that may include delusions, auditory and visual hallucinations, paranoia, agitation, or excessive activation. It is also a drug which is used effectively for bipolar disorder and the mania which comes with it. Sometimes it can assist with the depressive states of bipolar.

Stopping prescribed olanzapine could be a bad idea for you, depending on what it is treating. Coming off antipsychotic or antimanic class of drugs has the potential to cause you big problems depending on how necessary they are for you.

It is a serotonin 2A receptor antagonist as well, but this action actually helps keep dopamine action happening in other areas of the brain where dopamine is not causing problems. With the medical use of olanzapine, you only want to decrease dopamine in the mesolimbic cortex. The 5HT2A action is what makes this drug an "atypical" or "second generation" antipsychotic by helping restore dopamine activity in the other cortical pathways (not mesolimbic) to help stop down feelings which can be created by a 1st generation antipsychotic (blunting dopamine everywhere vs. blunting dopamine where it's needed).

The 5HT2A antagonist properties will block effects from psychedelic drugs. However, this action helps make the drug not as anti-dopaminergic as previous similar drugs which used to be more commonly used.

Olanzapine is a Dopamine-2 receptor antagonist. This will cause some blunting the ability to feel good/sense of reward from other drugs which stimulate dopamine. This includes cigarettes, but coffee not really. With gabapentin, olanzapine will not block any of the action of gabapentin, at least in terms of medical usage. I suppose it is possible for gabapentin to lead to some dopamine release, but if so, not much.

You are likely taking the olanzapine for something going on in the brain which is characterized by excess dopamine. Usually this medicine is prescribed for psychotic disorders that may include delusions, auditory and visual hallucinations, paranoia, agitation, or excessive activation. It is also a drug which is used effectively for bipolar disorder and the mania which comes with it. Sometimes it can assist with the depressive states of bipolar.

Stopping prescribed olanzapine could be a bad idea for you, depending on what it is treating. Coming off antipsychotic or antimanic class of drugs has the potential to cause you big problems depending on how necessary they are for you.

It is a serotonin 2A receptor antagonist as well, but this action actually helps keep dopamine action happening in other areas of the brain where dopamine is not causing problems. With the medical use of olanzapine, you only want to decrease dopamine in the mesolimbic cortex. The 5HT2A action is what makes this drug an "atypical" or "second generation" antipsychotic by helping restore dopamine activity in the other cortical pathways (not mesolimbic) to help stop down feelings which can be created by a 1st generation antipsychotic (blunting dopamine everywhere vs. blunting dopamine where it's needed).

The 5HT2A antagonist properties will block effects from psychedelic drugs. However, this action helps make the drug not as anti-dopaminergic as previous similar drugs which used to be more commonly used.

IIRC gabapentin causes a downstream release of dopamine in the nucleus accumbens. Correct me if I am wrong though PharmSauce!

@harrytroy93: PharmSauce brings up a good point i neglected to mention. if your taking zyprexa for mental health reasons it's probably best to not stop taking it just so you can use substances. consulting with one's psychiatrist is your best option in this matter. managing one's symptoms is optimal.

this is some info but i'm not in a lab all day so i can't give you exact details:

typically the 4 psych med injections that are similar in the debilitating way people suffer are invega/xeplion, zyprexa/olanzapine, abilify/aripiprazole and haldol/haloperidol. some people have taken the pill form of one of the aforementioned and had negative interactions as well, more rare when that happens but it does. risperdal/risperidone has been known to cause this as well but not as frequently in people and should also be noted that it did hit the market before invega/xeplion but it is not the same thing. risperdal/risperidone's active ingredient is paliperidone which is what invega is, basically invega is risperdal but in more potent form and people have had varying results in both substance use and therapeutic values while taking it.

these 4 medications all have 4 receptors they target in common: D (2) dopamine receptor, D (1A) dopamine receptor, D (3) dopamine receptor and 5-hydroxytrytamine2A or 5HT2A receptor. it is one of these that when disabled that no matter what med you are taking or what other substance you are taking and what parts of the brain they affect; you will no longer be able to experience them until that receptor wakes back up again. it is believed to be the 5HT2A receptor that affects one's experience of substances in this manner. so it's not blocking the coffee, cigs and GABA; it's disabling a receptor that allows you to experience the effects from them.

your lucky compared to others, if it was fully disabled you wouldn't feel pleasure at all. it's called anhedonia, a state of emotionless being and inability to feel pleasure. maybe only slightly feeling GABA, coffee and cigs while taking zyprexa is better than not feeling them at all.

from personal experience: i took over 100+ mg's of zyprexa pills for two years when i was younger. i had very lil to any side effects/withdrawal symptoms at all. other people who took it and gave me feedback since i was first on it mentioned to many varying degrees what your talking about, like some could feel coffee, some felt it diminished and some not at all. and other complications like head aches, weight gain, sleep problems. hence why i suggested you look into the list of side effects and get to hear what other people have experience as well.

if you continue to take zyprexa and find something that helps you to feel the GABA or any other substance again please post here or PM me with the info. it would benefit many people not only on zyprexa but also might help them on one of the other 3 meds as well.

i wanna be able to feel the effects of the other medicines im not trying to get high but i want to feel the effects of the medicine euphoria and eveything

Most every drug is going to be blunted by Olanzapines effects on the brain like Invegauser stated. It is designed to shut down dopamine receptors, which play a significant role in the euphoria of drugs.